Ring diameter variator for ring-shaped accessory

ABSTRACT

A ring diameter variator for a ring-shaped accessory includes a case that has first and second pull-out ports in opposite end parts, a reel that is rotatably housed within the case, first and second adjustment straps that are each wound up in the same direction by the reel and pulled outward through the first and second pull-out ports and that are connected to one end and the other end of the ring-shaped accessory, and a spiral spring that rotatingly urges the reel in a wind-up direction of the first and second adjustment straps. Thus, it is possible to provide a ring diameter variator for a ring-shaped accessory that enables sufficient enlargement of ring diameter and that has a good appearance.

TECHNICAL FIELD

The present invention relates to an improvement of a ring diameter variator for a ring-shaped accessory, the ring diameter variator being connected between one end and the other end of the ring-shaped accessory such as a necklace or a bracelet so as to make the ring diameter of the ring-shaped accessory variable.

BACKGROUND ART

Many ring-shaped accessories are equipped with a joint that enables them to be put on and taken off the body, but the operation of separating and connecting the joint is very cumbersome. Therefore, a ring diameter variator for a ring-shaped accessory that makes the ring diameter of the ring-shaped accessory variable so that, when being put on the body, the ring diameter is enlarged to make it easy to put on, and after being put on the ring diameter is returned to normal, has been already reported as disclosed in for example Patent Document 1.

RELATED ART DOCUMENTS Patent Documents

Patent Document 1: Japanese Patent Application Laid-open No. 2001-252113

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, in the ring diameter variator for a ring-shaped accessory disclosed in Patent Document 1 above, an expandable mechanism involving a coil spring is disposed partway along the ring-shaped accessory; such an arrangement using a coil spring cannot give sufficient enlargement of the ring diameter, and putting it on the body might be difficult. In order to obtain sufficient enlargement of the ring diameter, increasing the overall length of the coil spring could be considered, but this would make the length of a tubular case housing the coil spring longer, and the appearance as an accessory would be impaired, which is undesirable.

The present invention has been accomplished in light of such circumstances, and it is an object thereof to provide a ring diameter variator for a ring-shaped accessory that enables sufficient enlargement of ring diameter and that has a good appearance.

Means for Solving the Problems

In order to attain the above object, according to a first aspect of the present invention, there is provided a ring diameter variator for a ring-shaped accessory that is connected between one end and the other end of the ring-shaped accessory to make the ring diameter of the ring-shaped accessory variable, characterized in that the variator comprises a case that has first and second pull-out ports in opposite end parts, a reel that is rotatably housed within the case, first and second adjustment straps that are each wound up in the same direction by the reel and pulled outward through the first and second pull-out ports and that are connected to one end and the other end of the ring-shaped accessory, and a spiral spring that rotatingly urges the reel in a wind-up direction of the first and second adjustment straps.

Further, according to a second aspect of the present invention, in addition to the first aspect, the spiral spring is housed in a cylindrical spring chamber formed in an interior of the reel.

Furthermore, according to a third aspect of the present invention, in addition to the second aspect, a fixed shaft extending through the spring chamber is fixedly supported on the case, a flat face is formed on one side of the fixed shaft, a slit opens on the flat face, an inner end portion of the spiral spring is bent in the radially inward direction while being rounded and is engaged with the slit, and a rounded bent portion of the inner end portion is disposed in a crescent-shaped space formed between the flat face and an inner peripheral face of the spiral spring wound around the fixed shaft.

Moreover, according to a fourth aspect of the present invention, in addition to any one of the first to third aspects, first and second cutouts are provided in first and second reel flanges provided at opposite ends of the reel, first and second channels communicating with the first and second cutouts are formed in outer end faces of the first and second reel flanges, and inner end portions of the first and second adjustment straps are run respectively through the first and second cutouts, housed in the first and second channels, and adhered thereto.

Effects of the Invention

In accordance with the first aspect of the present invention, since the ring diameter variator includes the case that has the first and second pull-out ports in opposite end parts, the reel that is rotatably housed within the case, the first and second adjustment straps that are each wound up in the same direction by the reel and pulled outward through the first and second pull-out ports and that are connected to one end and the other end of the ring-shaped accessory, and the spiral spring that rotatingly urges the reel in the wind-up direction of the first and second adjustment straps, the total amount of the first and second adjustment straps pulled out corresponds to twice the number of rotations of the reel, and it is possible with a sufficient total amount of the first and second adjustment straps pulled out to sufficiently increase the ring diameter of the ring-shaped accessory, thus enabling it to be easily put on the neck, etc. of the user. Furthermore, compared with a case in which a single adjustment strap is wound around a reel and the adjustment strap is pulled out by the same amount as the above total amount pulled out, the number of rotations of the reel can be halved, the amount of the spiral spring wound in is also halved, and the durability can be enhanced effectively. Moreover, since the reel and the spiral spring are circular and compact, the case housing same can also be made compact, and not only does the ring-shaped accessory have a good appearance, but it is also possible to use the case as a fashionable pendant.

In accordance with the second aspect of the present invention, since the spiral spring is housed in the cylindrical spring chamber formed in the interior of the reel, dead space in the interior of the reel can be utilized for placement of the spiral spring, and it is possible to prevent the case from being increased in dimensions due to placement of the spiral spring, thus making the case more compact.

In accordance with the third aspect of the present invention, since the fixed shaft extending through the spring chamber is fixedly supported, the flat face is formed on one side of the fixed shaft, the slit opens on the flat face, the inner end portion of the spiral spring is bent in the radially inward direction while being rounded and is engaged with the slit, and the rounded bent portion of the inner end portion is disposed in the crescent-shaped space formed between the flat face and the inner peripheral face of the spiral spring wound around the fixed shaft, even when the spiral spring is wound around the outer periphery of the fixed shaft, it is possible to avoid effectively a load being concentrated on the bent portion of the inner end portion of the spiral spring, thus preventing the bent portion from breaking and thereby enhancing the durability of the spiral spring.

In accordance with the fourth aspect of the present invention, since the first and second cutouts are provided in the first and second reel flanges provided at opposite ends of the reel, the first and second channels communicating with the first and second cutouts are formed in the outer end faces of the first and second reel flanges, and the respective inner end portions of the first and second adjustment straps run through the first and second cutouts, are housed in the first and second channels, and adhered, the respective inner end portions of the first and second adjustment straps are connected in a state in which they are embedded in the reel, and it is possible to prevent peeling off due to interference with adjacent components, thus enhancing the durability of the first and second adjustment straps, and thereby making it possible to wind in the first and second adjustment straps neatly into the reel groove without interfering with the inner end portions.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a front view showing a necklace equipped with the ring diameter variator of the present invention in a state in which it has been put on a user. (first embodiment)

FIG. 2 is a view, corresponding to FIG. 1, showing the process via which the necklace is put on a user. (first embodiment)

FIG. 3 is a longitudinal enlarged front view of the ring diameter variator showing a state in which first and second adjustment straps are wound in. (first embodiment)

FIG. 4 is a view, corresponding to FIG. 3, showing a state in which the first and second adjustment straps are pulled out. (first embodiment)

FIG. 5 is a sectional view along line 5-5 in FIG. 3. (first embodiment)

FIG. 6 is a sectional view along line 6-6 in FIG. 5. (first embodiment)

FIG. 7 is a sectional view along line 7-7 in FIG. 3. (first embodiment)

FIG. 8 is a sectional view along line 8-8 in FIG. 3. (first embodiment)

FIG. 9 is a sectional view along line 9-9 in FIG. 3. (first embodiment)

EXPLANATION OF REFERENCE NUMERALS AND SYMBOLS

-   A Wind-up direction -   B Pull-out direction -   1 Ring-shaped accessory (necklace) -   3 Case -   4 Reel -   5 a First adjustment strap -   5 a 1 Inner end portion of first adjustment strap -   5 b Second adjustment strap -   5 b 1 Inner end portion of second adjustment strap -   6 Spiral spring -   6 a Inner end portion of spiral spring -   6 a 1 Bent portion of the inner end portion -   9 a First pull-out port -   9 b Second pull-out port -   12 a First reel flange -   12 b Second reel flange -   13 Adhesive -   14 a First cutout -   14 b Second cutout -   15 a First channel -   15 b Second channel -   18 Spring chamber -   19 Fixed shaft -   20 Slit -   21 Space

MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention is explained below by reference to the attached drawings.

FIRST EMBODIMENT

First, in FIG. 1 and FIG. 2, a necklace 1 as a ring-shaped accessory has a first joint 1 a and a second joint 1 b at one end and the other end thereof, and a ring diameter variator 2 that can adjust the ring diameter of the necklace 1 is connected between the first and second joints 1 a and 1 b.

As shown in FIG. 3 to FIG. 4, the ring diameter variator 2 is formed from a case 3, a reel 4 that is housed in the case 3, first and second adjustment straps 5 a and 5 b that are wound up by the reel 4, and a spiral spring 6 that rotatingly urges the reel 4 in the wind-up direction of the first and second adjustment straps 5 a and 5 b. The rotational direction of the reel 4 for winding up the adjustment straps 5 a and 5 b is called a wind-up direction A, and the rotational direction opposite thereto is called a pull-out direction B.

The case 3 is formed from first and second case half bodies 3 a and 3 b whose open faces on end faces thereof abut against each other, and has an eye shape when viewed from the front. A plurality of positioning bosses 7 (see FIG. 3 and FIG. 8) are formed on the abutment face of the first case half body 3 a, a plurality of positioning projections 8 are formed on the abutment face of the second case half body 3 b, and the two case half bodies 3 a and 3 b are joined by press fitting the positioning bosses 7 and the positioning projections 8. In this process, the press-fitted parts may be coated with an adhesive.

First and second bearing bosses 10 a and 10 b opposing each other across a gap are formed integrally with central parts of the first and second case half bodies 3 a and 3 b, and the reel 4 is rotatably supported on outer peripheral faces of the first and second bearing bosses 10 a and 10 b. This reel 4 has at opposite ends first and second reel flanges 12 a and 12 b defining an annular reel groove 11 on the outer periphery, and a pair of first and second adjustment straps 5 a and 5 b are wound around the reel groove 11 as follows.

That is, as shown in FIG. 3 and FIG. 7, the first reel flange 12 a is provided with a first cutout 14 a, a first channel 15 a communicating with the first cutout 14 a is formed in an outer end face of the first reel flange 12 a, and an inner end portion 5 a 1 of the first adjustment strap 5 a runs through the first cutout 14 a, is housed in the first channel 15 a, and is adhered with an adhesive 13.

Furthermore, the second reel flange 12 b is provided with a second cutout 14 b at a position symmetrical to the first cutout 14 a, a second channel 15 b communicating with the second cutout 14 b is formed in an outer end face of the second reel flange 12 b, and an inner end portion 5 b 1 of the second adjustment strap 5 b runs through the second cutout 14 b, is housed in the second channel 15 b, and is adhered with an adhesive 13. By so doing, the first and second adjustment straps 5 a and 5 b having the respective inner end portions 5 a 1 and 5 b 1 connected to the first and second reel flanges 12 a and 12 b are wound in the same direction on the reel groove 11, and connecting terminals 5 a 2 and 5 b 2 at outer end parts thereof are pulled outward from first and second pull-out ports 9 a and 9 b provided at opposite ends of the case 3 (see FIG. 3 and FIG. 9) and are connected to the first and second joints 1 a and 1 b respectively.

As shown in FIG. 6, hollow parts of the bearing bosses 10 a and 10 b serve as segment-shaped support holes 17 and 17, and opposite end parts of a fixed shaft 19 extending through a cylindrical spring chamber 18 in the interior of the reel 4 are fixedly supported by the support holes 17 and 17. This fixed shaft 19 has a cross section corresponding to the cross section of the segment-shaped support holes 17 and 17. That is, it has a flat face 19 a on one side face, and a slit 20 is provided in the fixed shaft 19 so as to open on the flat face 19 a. This slit 20 is formed throughout the entire length of a portion, excluding the one end part supported on one bearing boss 10 a or 10 b.

Referring again to FIG. 3 to FIG. 5, the spiral spring 6 is housed in the cylindrical spring chamber 18 in the interior of the reel 4. In this arrangement, an inner end portion 6 a of the spiral spring 6 is bent in a radially inward direction and is latched into the slit 20 of the fixed shaft 19, a bent portion 6 a 1 thereof is rounded and disposed in the region of the flat face 19 a, and the rounded bent portion 6 a 1 is thereby disposed in a crescent-shaped space 21 formed between the flat face 19 a and an inner peripheral face of the spiral spring 6 wound around the fixed shaft 19 (see FIG. 4).

An outer end portion 6 b of the spiral spring 6 is bent in a radially outward direction as a hook shape and is latched into a slit 22 provided in the reel 4. The spiral spring 6 is arranged so that the resilient force in its expansion direction rotatingly urges the reel 4 in the wind-up direction A for the first and second adjustment straps 5 a and 5 b.

The operation of this embodiment is now explained.

In the ring diameter variator 2, as shown in FIG. 3 the spiral spring 6 usually expands to rotate the reel 4 in the wind-up direction A and make the first and second adjustment straps 5 a and 5 b be wound in into the reel groove 11 of the reel 4, thus holding the first and second joints 1 a and 1 b of the necklace 1 at the positions of the first and second pull-out ports 9 a and 9 b of the case 3, and at this time the necklace 1 is in a state in which the ring diameter is a minimum.

When the necklace 1 is put on, as shown in FIG. 2 a user U grips and pulls parts in the vicinity of the first and second joints 1 a and 1 b of the necklace 1 with both hands, the first and second adjustment straps 5 a and 5 b are pulled outside the case 3 through the pull-out ports 9 a and 9 b, and accompanying this as shown in FIG. 4 the reel 4 makes the spiral spring 6 decrease in diameter while rotating in the pull-out direction B, thereby accumulating an expansion force.

When due to the first and second adjustment straps 5 a and 5 b being pulled out the ring diameter of the necklace 1 increases to more than the diameter of a head part H of the user U, the user U can easily put on the necklace 1 from the head part H to a neck part N. After being put on the pulling-out force for the first and second adjustment straps 5 a and 5 b is released, the spiral spring 6 makes the reel 4 rotate in the wind-up direction B by virtue of the accumulated expansion force, and the reel 4 winds in the first and second adjustment straps 5 a and 5 b into the reel groove 11 at the same time, thereby making the ring diameter of the necklace 1 its usual minimum diameter.

As described above, since the ring diameter variator 2 of the present invention includes the case 3 that has the first and second pull-out ports 9 a and 9 b in opposite end parts, the reel 4 that is rotatably housed within the case 3, the first and second adjustment straps 5 a and 5 b that are each wound up in the same direction by the reel 4 and pulled outward through the first and second pull-out ports 9 a and 9 b and that are connected to one end and the other end of the necklace 1, and the spiral spring 6 that rotatingly urges the reel 4 in the wind-up direction A of the first and second adjustment straps 5 a and 5 b, the total amount of the first and second adjustment straps 5 a and 5 b pulled out corresponds to twice the number of rotations of the reel 4, and it is possible with a sufficient total amount of the first and second adjustment straps 5 a and 5 b pulled out to sufficiently increase the ring diameter of the necklace 1, thus enabling it to be easily put on the neck N of the user U. Furthermore, compared with a case in which a single adjustment strap is wound around a reel and the adjustment strap is pulled out by the same amount as the above total amount pulled out, the number of rotations of the reel 4 can be halved, the amount of the spiral spring 6 wound in is also halved, and the durability can be enhanced effectively.

Moreover, since the reel 4 and the spiral spring 6 are circular and compact, the case 3 housing same is also circular or nearly so and compact, and not only does the necklace 1 have a good appearance, but it is also possible to use the case 3 as a fashionable pendant.

Furthermore, since the spiral spring 6 is housed in the cylindrical spring chamber 18 formed in the interior of the reel 4, dead space in the interior of the reel 4 can be utilized for placement of the spiral spring 6, and it is possible to prevent the case 3 from being increased in dimensions due to placement of the spiral spring 6, thus making the case 3 more compact.

Moreover, since the fixed shaft 19 extending through the spring chamber 18 is fixedly supported, the flat face 19 a is formed on one side of the fixed shaft 19, the slit 20 opens on the flat face 19 a, the inner end portion 6 a of the spiral spring 6 is bent in the radially inward direction while being rounded and is engaged with the slit 20, and the rounded bent portion 6 a 1 of the inner end portion 6 a is disposed in the crescent-shaped space 21 formed between the flat face 19 a and the inner peripheral face of the spiral spring 6 wound around the fixed shaft 19, even when the spiral spring 6 is wound around the outer periphery of the fixed shaft 19, it is possible to avoid effectively a load being concentrated on the bent portion 6 a 1, thus preventing the bent portion 6 a 1 from breaking and thereby enhancing the durability of the spiral spring 6.

Furthermore, since the first and second cutouts 14 a and 14 b are provided in the first and second reel flanges 12 a and 12 b provided at opposite ends of the reel 4, the first and second channels 15 a and 15 b communicating with the first and second cutouts 14 a and 14 b are provided in the outer end faces of the first and second reel flanges 12 a and 12 b, and the respective inner end portions 5 a 1 and 5 b 1 of the first and second adjustment straps 5 a and 5 b run through the first and second cutouts 14 a and 14 b, are housed in the first and second channels 15 a and 15 b, and adhered, the respective inner end portions 5 a 1 and 5 b 1 of the first and second adjustment straps 5 a and 5 b are connected in a state in which they are embedded in the reel 4, and it is possible to prevent peeling off due to interference with adjacent components, thus enhancing the durability of the first and second adjustment straps 5 a and 5 b, and thereby making it possible to wind in the first and second adjustment straps 5 a and 5 b neatly into the reel groove 11 without interfering with the inner end portions 5 a 1 and 5 b 1.

The present invention is not limited to the above embodiment and may be modified in a variety of ways as long as the modifications do not depart from the spirit and scope thereof. For example, the ring diameter variator of the present invention may be applied to a bracelet. Furthermore, the case 3 may be formed into a polygon. Moreover, as the first and second adjustment straps 5 a and 5 b silkworm gut or a chain may be used. 

1. A ring diameter variator for a ring-shaped accessory that is connected between one end and the other end of the ring-shaped accessory to make the ring diameter of the ring-shaped accessory variable, wherein the variator comprises a case that has first and second pull-out ports in opposite end parts, a reel that is rotatably housed within the case, first and second adjustment straps that are each wound up in the same direction by the reel and pulled outward through the first and second pull-out ports and that are connected to one end and the other end of the ring-shaped accessory, and a spiral spring that rotatingly urges the reel in a wind-up direction of the first and second adjustment straps.
 2. The ring diameter variator for a ring-shaped accessory according to claim 1, wherein the spiral spring is housed in a cylindrical spring chamber formed in an interior of the reel.
 3. The ring diameter variator for a ring-shaped accessory according to claim 2, wherein a fixed shaft extending through the spring chamber is fixedly supported on the case, a flat face is formed on one side of the fixed shaft, a slit opens on the flat face, an inner end portion of the spiral spring is bent in the radially inward direction while being rounded and is engaged with the slit, and a rounded bent portion of the inner end portion is disposed in a crescent-shaped space formed between the flat face and an inner peripheral face of the spiral spring wound around the fixed shaft.
 4. The ring diameter variator for a ring-shaped accessory according to claim 1, wherein first and second cutouts are provided in first and second reel flanges provided at opposite ends of the reel, first and second channels communicating with the first and second cutouts are formed in outer end faces of the first and second reel flanges, and inner end portions of the first and second adjustment straps are run respectively through the first and second cutouts, housed in the first and second channels, and adhered thereto.
 5. The ring diameter variator for a ring-shaped accessory according to claim 2, wherein first and second cutouts are provided in first and second reel flanges provided at opposite ends of the reel, first and second channels communicating with the first and second cutouts are formed in outer end faces of the first and second reel flanges, and inner end portions of the first and second adjustment straps are run respectively through the first and second cutouts, housed in the first and second channels, and adhered thereto.
 6. The ring diameter variator for a ring-shaped accessory according to claim 3, wherein first and second cutouts are provided in first and second reel flanges provided at opposite ends of the reel, first and second channels communicating with the first and second cutouts are formed in outer end faces of the first and second reel flanges, and inner end portions of the first and second adjustment straps are run respectively through the first and second cutouts, housed in the first and second channels, and adhered thereto. 